Lamp socket



July 14, 1936. JQHNSQN 2,047,563

LAMP SOCKET Filed Jan. 24, 1933 mMmM/Jmm A 7'TL7/FNEY.

Patented July 14, 1936 UNITED v STATES PATENT orrica LAMP SOCKET v Gustaf A. Johnson, New Bedford, Mass.

Application January 24, 1938, Serial No. 653,220

3 Claims. (01. 173- 355) This invention relates to electric lamp sockets and more particularly to a lamp socket designed for use as a portable light.

Heretofore, in the use of portable lights, it has 5 been customary to attach an electric lamp socket of any suitable construction to the end of an electric light cord of suitable length, the cord being made up of a pair of insulated conductors twisted together and the other end of the cord being provided with a plug for insertion in a suitable receptacle. Portable lamp sockets of this character are frequently subjected to hard usage and the socket is liable to be injured or broken by being dropped on the floor or coming in contact with hard surfaces. Thisis especially true if the outer shell of the socket is made of porcelain or other brittle insulating material.

One of the important objects of the invention is the provision of a lamp socket of the foregoing character which is adapted to withstand hard usage and is not subject to breakage when dropped on a hard floor.

| Another object of the invention is the provision of a socket of simple construction provided with :5 an outer shell of flexible rubber composition enclosing the parts of the socket in stretched condition to eliminate other fastening means.

A further object of the invention is the provision of a socket of the above character in which 30 the usual enclosing shell of metal or porcelain or other insulating material is eliminated thereby enabling the socket to be made at a very low cost.

other objects of the invention will bemore specifically described and pointed out hereinafter.

85 My invention in its preferred form contemplates a lamp socket comprising a base of suitable insulating material carrying a lamp receiving screw shell of ordinary construction and a central lamp contact with a shell of resilient rubber en- 40 closing said parts in stretched condition. The base may be made in any suitable form and may be adapted to include a switch, preferably of the push button construction. To prevent corrosion between the rubber shell and the lamp receiving 45 screw shell an insulating cylinder of fibrous material such as paper may be mounted on the screw shell. The cylinder presents a smooth surface and facilitates the mounting of the rubber shell on the socket parts and also its removal if necessary.

50 A lamp socket of this construction is for all practical purposes unbreakable and is especially suited for use in garages and other places where portable lights are liable to be dropped on concrete floors and subjected to other hard usage.

66 The number of parts in the socket is reduced to a minimum since the usual enclosing shell is eliminated and the rubber shell is applied directly to the insulating base and the members carried by it. Since the rubber shell is stretched over these parts, there is no possibility of its becoming sepa- 6 rated therefrom and yet it may be easily removed if it becomes necessary to repair the inner parts of the socket.

In the accompanying drawing Fig. 1 is a view in perspective of a lamp socket of the keyless type 10 made in accordance with my invention; Fig. 2 is a central longitudinal sectional view of the same with the insulating base and part of the insulating cylinder shown in elevation; Fig. 3 is a perspective view of a lamp socket of the push button type constructed in accordance with my invention; and Fig. 4 is a central longitudinal sectional view of the same with the insulating base, push button. switch and part of the insulating cylinder shown in section.

In the drawing my invention is shown as embodied in two types of sockets, first, a keyless type (Figs. 1 and 2) in which the switch controlling the current is at a distance from the lamp socket and, second, a push button type (Figs. 3 and 4) in which the current is controlled by a push button switch in the socket itself. The only differences between these two types of sockets is in the form of the insulating base which in the second type is adapted to carry a push button switch and in the provision of suitable openings in the rubber shell for that type through which project the push buttons for operating the switch.

Referring particularly to Figs. 1 and 2, the keyless type of socket comprises an insulating base I0 carrying fastened to one face thereof a screw shell l2 of usual construction and a central lamp contact (not shown) which is also of usual construction. The insulating base is preferably made of porcelain, although it may be of any other suitable insulating material and the screw shell is of metal and serves as one of the contact members to complete the lamp circuit in the usual manner. The screw shell is threaded forreceiving the threaded butt of an electric lamp and on the screw shell is mounted a cylinder I6 of paper or other suitable insulating material. Enclosing the foregoing parts is a hollow rubber shell l8 which may be made of rubber or any suitable resilient material, the inner diameter of said shell being slightly less in dimension than the diameter of the insulating body and the other parts so that when it is mounted on those parts it is required to be in stretched condition in order to grip said parts firmly to prevent casual withdrawal or separation.

As shown the insulating body is in the form of a thickened disk having on one side of its periphery a curved depression 20 in which lies an extended portion 22 of the screw shell I2 adapted to carry a binding screw 24 for attachment of one of the current carrying insulated wires 26. The other insulated wire 28 is connected to the central contact in any suitable manner and these two wires which are twisted together to form the cord may be covered with an insulated cylindrical jacket III of rubber composition or other material. At its base end the rubber shell is provided with a bored hub portion 32 for the insertion of the electric cord or wires.

The rubber shell may be made in any suitable form but preferably its walls adjacent its opening are of less thickness than the walls of its remaining portion in order to facilitate the rolling back of the shell at its opening and the stretching of it to remove the inner parts of the socket if that becomes necessary for making repairs in those parts. Preferably the insulating base is of slightly larger diameter than the screw shell so that the cylinder of insulating material is seated on one face of the insulating body and after the parts are mounted within the rubber shell the slightly larger diameter of the insulating body induces greater stretch of that portion of the rubber shell and holds the socket parts firmly within the shell. The insulating cylinder mounted on the screw shell not only presents a smooth surface which facilitates the mounting of the socket parts within the rubber shell but it also prevents contact between the inner surface of the shell and the metal screw shell thereby eliminating any corrosion which might ensue from rubber contacting with metal and any deterioration of the parts. Preferably the insulating cylinderand the rubber shell at the open end of the socket extend a slight distance-beyond the end of the screw shell.

In the second type of socket (Figs. 3 and 4) the insulating base is made up of two disks or buttons 34 and 36 which are fastened together in separated relation by a pair of brackets only one of which 38 is shown in Fig. l, the other being on the opposite side. Buttons 34 and 36 are made of porcelain or any other suitable insulating material and the brackets are of metal or other conducting material. Fastened to the outer face of button 36 is a threaded lamp receiving screw shell l2 and mounted on said screw shell and seated against the outer face of button 36 is an insulating cylinder l6. In the space between the two buttons may be arranged a push button switch of any suitable construction and such a switch is shown generally but not specifically in Fig. 4 of the drawing.

The said switch' comprises a rockable member 40 pivotal mounted at its lower end and actuated by a. spring connected to a slide member 42 having push buttons 44 and 48 on the two upturned ends. The slide is mounted in the upturned ends of a U-shaped supporting member 4a, I one position the movable member 40 engages a fixed contact 52 in the upper button for closing the circuit and in the other position it is thrown in the opposite direction and breaks the circuit. The rubber shell is provided with two oppositely disposed circular openings for permitting the push buttons to project therethrough outwardly and when the shell is mounted on the socket parts, it is spread to snap over the push buttons.

It will be observed that the parts of the socket other than the rubber shell have been reduced to a minimum number thereby permitting a rapid assembling of the parts. These parts are all assembled as a unit and in mounting the rubber shell on said unit the conductor wires are passed through the opening in the bored'hub of the shell fastened to the appropriate parts in the socket unit and the shell is then expanded to receive the socket unit, the conductors being drawn outwardly through the bored hub during this operation. The mounting of the rubber shell on the socket unit may be accomplished very rapidly by providing proper tools for expanding it to take the unit and withdrawing the tools and allowing it to. snap back in place on the unit. It is important in this connection that the rubber shell should be sufficiently flexible to permit this operation and yet have sufficient tensile strength to grip firmly the socket unit.

It is further to be noted that a lamp socket of the character described may, by the use of my invention, be made in very small compact form so that it is adapted for household use. One feature which contributes to this compactness is the provision of an insulating body in which the terminals are arranged in suitable recesses in the sides of said insulating body, which permits the insulating body to be seated in close proximity to the base of the rubber shell, thereby reducing the length of the shell and avoiding the lost space between the insulating body and the rubber shell, which is necessitated when the terminals are mounted on the bottom face of the base of the insulating body.

Although I have shown the switch type of socket as adapted to be operated by a switch of the push button construction, a switch operated by a key or a pull chain or any other operating device may be used instead of the push button switch by providing suitable openings in the outer shell to permit the operating member to project therethrough.

It is to be understood that my invention may be embodied in other forms of construction than that described all within the purview of the following claims.

What I claim is:

1. A lamp socket of the character described, comprising an insulating body, a lamp receiving screw shell fastened to the outer face of said body and being of slightly smaller outside diameter than the diameter of said body to provide an annular shoulder surrounding said screw shell on the outer face of said body, a corrosion preventing cylinder mounted on and enclosing said screw shell and seated on said shoulder, a relatively thick shell of rubber composition mounted on and enclosing said insulating body and said cylinder, the inside diameter of said composition shell being smaller than the outside diameters of said body and said cylinder whereby said composition shell is in stretched condition when mounted on said body and said cylinder in order to tightly engage and hold the same to provide a waterproof and non-breakable structure, said insulating body being provided with oppositely disposed side receses of sufiicient depth for accommodating a pair of terminals and lead wires connected thereto, said side recesses permitting said insulating body to be seated in close proximity to the bottom of said rubber shell to produce a small compact structure.

2. A lamp socket of the character described,,

comprising a relatively thick base oi! insulating material having a periphery parallel to its center axis, a lamp receiving screw shell fastened to the outer face of said base and of less diameter than said base to provide an annular shoulder on said outer face, a corrosion preventing cylinder mounted on and enclosing said screw shell and being seated on said shoulder, a relatively thick shell of resilient rubber composition mounted on and enclosing said base and said cylinder, the inside diameter of said composition shell being smaller than the outside diameters of said base and saidcylinder whereby said composition shell is in stretched condition on said base and said cylinder in order to tightly engage and hold same to provide a waterproof and non-breakable structure, said base being provided with oppositely disposed side recesses of suiiicient depth for accommodating a pair of terminals and lead wires mounted therein, saidrecesses permitting said base to be seated in close proximity to the bottom of said composition shell to provide a small compact structure suitable for household use.

3. A lamp socket or the character described having, in combination, an insulating body comprising a pair of insulating buttons fastened together in spaced relation, a push button switch mounted between said buttons, a lamp receiving screw shell fastened to the outer face of one of said buttons and of less diameter than said button to provide an annular shoulder on said outer face, a corrosion preventing cylinder mounted on said screw shell and seated on said shoulder and a shell of relatively thick rubber composition mounted on and tightly enclosing said insulating body and cylinder, said rubber shell being provided with side openings for the push buttons of said switch and with an opening in its base for the passage of conductors, the inside diameter of said composition shell being smaller than the outside diameters of said enclosed parts whereby said composition shell is in stretched condition on the same in order to provide a waterproof and non-breakable structure, said insulating body being provided with a pair of oppositely disposed side terminals for attachment of lead wires thereto, said side terminals being inset between said insulating buttons and the inner of said buttons being provided with oppositely disposed side recesses for the lead wires attached to said side terminals, thereby permitting said insulating body to be seated in close proximity to the base of said rubber shell to make a small compact structure suitable for household use.

GUSTAF A. JOHNSON. 

